Address blocks  for Letters and Envelopes:

• Always use Mr., Mrs., Ms., Dr. or other applicable title before a personal name. 
  Example:  Mr. John Smith, not John Smith.
• Always use the two letter abbreviation for names of states.
  Example:  MI, not Michigan.
• Use of the nine-digit zip code is preferred when it is known.
  Example: 48109-2102, not 48109.
• An over-all example would look like this:
  Mr. John Smith
  1221 Beal Ave.
  Ann Arbor, MI 48109-2102